Gaya APA

Wolfram, W., Schilling, N. (2016). American English: dialects and variation. (3rd Ed.). John Wiley, USA: Wiley-Blackwell.

Gaya MLA

Wolfram, Walt., Schilling, Natalie. "American English: dialects and variation.". 3rd Ed. John Wiley, USA: Wiley-Blackwell, 2016. Text.